Free AI Plagiarism Checker

Plagiarism means presenting someone else’s words or ideas as your own without appropriate acknowledgment. Changing a few words does not remove the need to cite the underlying idea. Correctly marked and referenced quotations are different from unattributed copying.

There is no universal number of consecutive words that makes a passage plagiarism. Distinctive wording, borrowed ideas, quotations, attribution and context all matter. A mechanical word-count threshold is not a reliable rule.

There is no universally acceptable plagiarism percentage. A similarity score may include properly cited quotations or standard terminology, while a small match can still be important. Review the actual passages and follow your institution’s requirements.

A checker compares text with available sources and flags similarities for review. The coverage and matching method affect what it can find. You still need to inspect the source, quotation marks and citation context.

Consequences depend on the assignment, institution, circumstances and applicable procedure. If you find a problem before submission, correct it and seek guidance where needed. A software flag alone does not determine an academic penalty.

Mimir Mentor combines source comparison with separate AI-writing and correction reports. Premium source analysis helps you inspect direct matches, close paraphrases and translation-related similarities against available academic and web sources.

The document score summarizes the tool’s findings. It is not a grade, a guarantee that every issue was found, or a prediction of your institution’s decision. Use it to organize a closer review.

Similarity describes overlap detected by a particular method against its available sources. It does not measure the percentage of a paper that is proven plagiarism. Look at the matched passages and their citations.

No. Plagiarism concerns attribution and use of sources; AI detection estimates patterns associated with generated writing. A human-written text can plagiarize, and AI-assisted text is not automatically plagiarized. Institutional AI rules are a separate question.

It is a model-based indication for that passage, not proof of who wrote it. False positives and false negatives are possible. Do not read a passage-level value as the proven AI-written share of the whole document.

Mimir compares against available academic publications and publicly accessible web sources. No checker has access to every private submission, paywalled text or unpublished document, so a check cannot establish exhaustive coverage.

The document workflow supports English, German and French. Choose a PDF or DOCX file and check the language and available scan options in the app before continuing.

The free overview is a starting point. Premium adds the detailed source comparison and report access described in the purchase flow. Do not assume that a free overview includes the same source analysis as a complete Premium scan.

You can start with the free features. Premium access and document scans have separate limits and purchase options. Check the price and scope displayed before confirming a purchase; see our plans for subscription details.

Open the suggested source, read the relevant passage and compare the meaning as well as the wording. Check quotation marks and attribution. Rewrite only where needed, then recheck the citation. Do not change correct quotations merely to reduce a score.